In some cases, such as driving or going to a bank or an airport for business, only one of hands is available for a wearer, and in such case, the spectacles can not be unfolded in convenience. In order to solve this problem, the inventor previously proposed two Chinese patent documents CN200810217846.5 and CN200910133429.7, titled “Automatically stretchable folding spectacles”, which connect a leg to a rim and a rim to a rim via three elastic members respectively, achieving that the stretchable folding spectacles can be completely unfolded with only one hand. However, in practice, both rims of the spectacles can not be stretched into a line, and in most cases only be stretched into a M-shaped profile, consequently, such spectacles are not convenient for use.